Air filter configured in a roll

ABSTRACT

The present disclosure relates to air filters. More particularly, it relates to adjustably sized air filter systems capable of use in a window opening. Some embodiments relate to a filter media assembly configured in a roll. In some embodiments, the filter media assembly includes a filter media having a leading end opposite a trailing end and first and second opposed side edges extending between the leading end and the trailing end.

TECHNICAL FIELD

The present disclosure relates to air filters. More particularly, itrelates to adjustably sized air filter systems capable of use in awindow opening.

BACKGROUND

Windows are available in a large variety of sizes and can includevertically or horizontally operable sashes to provide air flow betweenan exterior and an interior of a building structure. Occupants of abuilding structure often desire opening windows to let fresh air into aninterior of a home, business, or otherwise enclosed space. However, inmany locations, such as highly populated areas of China, the outside airis more contaminated than the indoor air. Novel filtering solutions areneeded to let the fresh aspects of the outdoor air in without letting inthe pollution or contaminants. Outdoor contaminants may include largerparticles such as pollen, dust, and mold spores and smaller particlessuch as those forming PM_(2.5), bacteria, and viruses. Gaseous outdoorpollutants such as odors, NO_(x), SO₂, ozone, and others may also be ofconcern in some locations.

SUMMARY

The inventors of the present disclosure recognized that, in light of theabove, a need exists for an air filter that protects users from airquality contaminants, allows fresh air get into the home throughwindows, can be easily installed and used by consumers, is versatile tofit in most locations, and/or has minimal impact on lighting andvisibility. In some embodiments, the filter is a window air filter.

The inventors of the present disclosure invented various embodiments ofair filters, methods of making air filters, and methods of using airfilters.

Some embodiments relate to an air filter comprising filter mediaassembly configured in a roll, the filter media assembly includingfilter media having a leading end opposite a trailing end and first andsecond opposed side edges extending between the leading end and thetrailing end.

In some embodiments, the air filter further comprises a housing forcontaining the filter media assembly. In some embodiments, the leadingedge can be releasably retained on at least one of the exterior orinterior of the housing. In some embodiments, the filter media assemblyis replaceable within the housing. In some embodiments, at least one ofthe leading edge and the trailing edge includes a looped structure, ahooked structure, and/or a fastening device. In some embodiments, thefirst end includes a handle. In some embodiments, the filter mediaassembly is retractable on the roll. In some embodiments, the rollincludes a central member that is under spring tension. In someembodiments, the central member provides stopping points. In someembodiments, the filter media assembly includes sufficient filter mediafor multiple uses. In some embodiments, the filter media assemblyincludes separation and/or perforation lines or points.

Some embodiments further include a hinged attachment mechanism. In someembodiments, the hinged attachment mechanism is combined with thehousing or attached to the central member. In some embodiments, thehinged attachment mechanism is rotatable.

In some embodiments, the filter media is at least one ofmoisture-resistant, moisture-repellant, electrostatically charged, anelectret nonwoven web, and/or not electrostatically charged. In someembodiments, the filter media includes at least one of carbon, activatedcarbon, a nonwoven, a thermoplastic, a thermosetting material, a porousfoam, fiberglass, paper, a high loft spunbound web, a low loft spunboundweb, a meltblown web, and/or bi-modal fiber diameter meltblown media. Insome embodiments, the filter media is pleated. In some embodiments, thefilter media is at least one of self-supporting and non-self-supporting.

Some embodiments further include a cutting device capable of cutting thefilter media to a desired size. In some embodiments, the cutting deviceis integrated into the housing.

In some embodiments, the air filter is a window air filter.

Some embodiments relate to a kit comprising an air filter as describedabove or herein and a cutting device capable of cutting the filter mediato a desired size. In some embodiments, the cutting device is integratedinto the housing.

Some embodiments relate to a kit comprising an filter as described aboveor herein and an attachment device capable of permanently orsemi-permanently attaching the air filter to a window. In someembodiments, the attachment device is at least one of a nail, a screw, ahook, an adhesive, and/or an adhesive backed interlocking strip.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an exemplary retractable air filter inaccordance with principles of the present disclosure;

FIG. 2A is a perspective view of an exemplary retractable air filter ina retracted state in accordance with principles of the presentdisclosure;

FIG. 2B is a perspective view of an exemplary retractable air filter ina un-retracted state in accordance with principles of the presentdisclosure;

FIG. 3 is a perspective view of an exemplary retractable air filter inaccordance with principles of the present disclosure;

FIGS. 4A-4C are perspective views of an exemplary retractable air filterfor use in, for example, a vertically opening window in accordance withprinciples of the present disclosure; and

FIG. 5 is a side view of an exemplary retractable air filter installedin, for example, a horizontally opening window in accordance withprinciples of the present disclosure.

DETAILED DESCRIPTION

Various embodiments and implementations will be described in detail.These embodiments should not be construed as limiting the scope of thepresent application in any manner, and changes and modifications may bemade without departing from the spirit and scope of the embodiments andimplementations. For example, many of the embodiments, implementations,and examples are discussed with specific reference to window airfilters, but these should not be construed to limit the applicationscope to this one exemplary implementation. Further, only some end useshave been discussed herein, but end uses not specifically describedherein are included within the scope of the present application. Assuch, the scope of the present application should be determined by theclaims.

One embodiment of a retractable filter 20 useable in a window inaccordance with principles of the present disclosure is illustrated inFIG. 1. The retractable filter 20 includes a filter media assembly 30having a filter media 32. In some embodiments, the filter media assembly30 can be in the form of a roll 33. In some embodiments, the filtermedia 32 is wound on a central member 34 and can be easily expanded andretracted (i.e. unrolled and rolled back up). Details on the variouscomponents are provided below.

In general terms, the adjustable length of the filter media assembly 30,due to the retractable nature, allows it to fit in a wide variety ofwindow sizes. The retractable filter 20 can be attached to a partiallyopened window. The retractable filter 20 can fit a wide variety ofwindow sizes. The retractable filter 20 can be employed in a partiallyopen window, where only 10-30% of the window area is blocked, forexample, leaving a large percentage of the window area still open forlight passage and visibility.

In some embodiments, a roll of filter media assembly 30 has a first, orleading, end 36 and a second, or trailing, end (not shown) opposite thefirst end 36 adjacent to a central member 34. First and second sideedges 38, 40 extend between the first end 36 and the second end. In someembodiments, the filter media assembly 30 is generally rectangular whenextended. In some embodiments, the first end 36 can include a handle 42for increased usability. In some embodiments, one or both of the firstand second side edges 38, 40 can include a looped structure (generallyindicated by dashed line 44) or other fastening device, as is discussedin more detail below.

As illustrated in FIGS. 2A-2B, in some embodiments, the central member34 may be contained within a housing 50. The housing 50 can be anysuitable shape for containing the roll 33 and/or providing expansion andretraction of the filter media assembly 30. Some exemplary shapedinclude rectangular or tubular. In some embodiments, the housing 50includes at least one side 52 and, optionally, top and bottom ends 54,56. In some embodiments, the leading end 36 of the filter media assembly30 is easily accessible to a user and/or can be releasably retained onan exterior or interior of the housing 50. In some embodiments, thefilter media assembly 30 is replaceable within the housing 50. In someembodiments, the filter media assembly 30 can be user replaceablewithout replacing the housing 50 and/or mounting components (see, e.g.,FIG. 3). In some embodiments, the filter media assembly 30 may also bereplaceable without requiring replacement of internal winding (e.g.spring) components. For example, a refill filter media assembly 30 mayslidably engage the central member 34 containing the winding components.The housing 50 can provide several benefits, such as, for example,improved seal between the filter media 32 and the window frame, improvedaesthetic design, and/or enhanced locations and surface area formounting the retractable filter 20 to the window structure. In someembodiments, the housing 50 provides a further benefit by firmlydefining and fixing the distance between the mounting members for thetwo ends of the media central roll 34, which aids in assembly versusrequiring the user to measure and install separate brackets.

In some embodiments, the filter media assembly 30 is retractable ontothe roll 33 and unwound, or expanded, from the roll 33, as indicated byarrow “A” of FIG. 2B. In some embodiments, the central member 34 can bea spring-wound inner shaft or similar structure to provideretractability of the filter media assembly 30. In some embodiments,when the user desires to use the retractable filter 20 in the window,the filter media assembly 30 is unrolled by pulling on the handle 42 ofthe leading end 36. In some embodiments, the filter media assembly 30unwinds from the central shaft member 34, which is under a springtension, as the user continues to pull. In one embodiment, the centralmember 34 and spring mechanism (not shown) can provide stopping points,where the length of the unwound filter media assembly 30 can betemporarily fixed, until the spring mechanism is re-engaged. When theuser wants to return the filter media assembly 30 to within the housing50 or otherwise retract the filter media assembly 30, for example toclose the window, the user re-engages the spring mechanism, whichre-winds the filter media assembly 30 back into the housing 50.

In some embodiments, the filter media assembly 30 includes filter media32 of suitable size to fit a wide variety of window dimensions. In someembodiments, the filter media assembly 30 may be longer than needed fora single use. In some embodiments, the filter media assembly 30 has alength suitable to provide for one or more filter media 32 changes, forexample, wherein the dirty filter media 32 is discarded, and a cleansegment of filter media 32 is unwound from the next section on thefilter media assembly 30. In some embodiments, the filter media assembly30 can be cut to expose a new length of clean filter media 32, providingfor multiple filter changes from a single filter media assembly 30. Withparticular reference to FIG. 2B, in some embodiments, the filter mediaassembly 30 includes a plurality of separation lines 60 to divide thefilter media assembly 30 into discrete filter lengths. In someembodiments, each separation line 60 can be formed from any number ofthrough-cuts suitable to provide separation. In one embodiment, theseparations lines 60 are perforated lines formed at positions along thefilter media assembly 30 corresponding to common window widths. Theseparation lines 60 can be at varying (e.g., increasing or decreasing)distances from one another or uniform distances. Additionally, oralternately, a cutting device (not shown) may be integrated into thehousing 50. Any cutting device may be used. In some embodiments, thecutting device can, for example, be a thin metal strip having a serratededge.

In some embodiments, the filter media assembly 30 may incorporate loopedstructures 44, for example, either integrally or by addition, such aslamination, into one or both of the first and second side edges 38, 40.The loop structure 44 may be mated to a hook structure (see, e.g., FIG.4A) which is applied to the window frame and/or sash members. In someembodiments, the combined hook/loop structure holds in the filter mediaassembly 30 in place and reasonably seals the side edges 38, 40 from airbypassing the filter media assembly 30. In some embodiments, low-profilehooks, such as used in diapers, may be used, preferably with an adhesiveback-side coating. In some embodiments, the hook and loop may bereversed in attachment orientation. In some embodiments, for example,where the retractable filter 20 is mounted in a recessed window, where agood mating edge for hook and loop attachment may not be available, theretractable filter 20 may include secondary strips or structures thatcan be attached to the window frame and/or sash to help facilitate theengagement. In some embodiments, the filter media 32 may also oralternatively be conformable, which will allow the filter media 32 toattach to hook structures in multiple planes.

FIG. 3 illustrates an exemplary retractable filter 20 including a hingedattachment mechanism 62, which may be combined with the housing 50 orwhich may be attached directly to the central member 34 at the roll 33and the window. In one embodiment, the hinge 62, or similar mechanism,is rotatable to allow the filter media assembly 30 to pivot away fromthe window when the filter media assembly 30 is not in use and swinginto the window when in use. This motion could allow for easier userinterface and help enable better sealing of the filter media assembly 30to the window cavity. In some embodiments, a locking mechanism (notshown) may be included to help retain the housing 50 in one or morerotated positions.

The particular filter media 32 selected for the filter media assembly 30can be particularly suited have any of the particular desiredcharacteristics described herein. In some embodiments, the filter mediaassembly 30 is constructed from moisture-resistant materials. In someembodiments, the filter media may include additional layers or featuresto specifically block or repel water, such as rain. In some embodiments,an electrostatic charge is optionally imparted into or onto material(s)of the filter media 32. In some embodiments, an electrostaticallycharged media 32 may be used, of which many grades are available, andmany of which offer high efficiency with low pressure drop. In someembodiments, the filter media 32 can be an electret nonwoven web.Electric charge can be imparted to the filter media 32 in a variety ofways as is well known in the art, for example by hydrocharging, coronacharging, etc. (e.g., as described in U.S. Pat. No. 7,947,142, theentirety of which is incorporated by reference herein).

In other embodiments, the filter media 32 is not electrostaticallycharged. In some embodiments, additional multi-functional media grades,which incorporate activated carbon or other materials for purifyinggas-phase pollutants, may also or alternatively be incorporated into thefilter structure. In some embodiments, the filter media 32 can beconstructed, for example, from nonwoven fibrous media formed ofthermoplastics or thermosetting materials such as polypropylene, linearpolyethylene and polyvinyl chloride. Other suitable, non-limitingmaterials for the filter media include porous foams, nonwovens, papers,fiberglass, or the like. In some embodiments, the filter media 32comprises a filter media that attracts and captures dust, allergens(such as pollen and mold spores), and/or fine particle pollution fromthe outdoor air.

Other nonwoven webs useful with the filter media 32 can be a high loftspunbond webs, such as described, for example, in U.S. Pat. No.8,162,153 to Fox et al., the entirety of which is incorporated herein.In other embodiments, the filter media 32 can be a low loft spunbondweb, such as is described in U.S. Pat. No. 7,947,142 to Fox et al., theentirety of which is incorporated herein. In yet other embodiments,nonwoven webs useful with the filter media 32 are generated by othertechniques and/or have other characteristics, such as the meltblownnonwoven webs disclosed in U.S. Pat. No. 6,858,297 to Shah et al., theentirety of which is incorporated herein. Other non-limiting example ofuseful nonwoven web formats include bi-modal fiber diameter meltblownmedia such as those described in U.S. Pat. No. 7,858,163, the entiretyof which is incorporated herein.

In some embodiments, the filter media 32 is an electrostatically chargednonwoven type of media. In some embodiments, the filter media 32 can bea pleated filter media including at least a portion that has been foldedto form a configuration comprising rows of generally parallel,oppositely oriented folds. In some embodiments, pleats can be formed inthe filter media 32 (or in the pleated filter media assembly 30) usingvarious methods and components as are well known in the art, e.g., toform a pleated filter for use in applications such as air filtration.,for example those described in U.S. Pat. No. 6,740,137 to Kubokawa etal. and U.S. Pat. No. 7,622,063 to Sundet et al., the entire teachingsof both of which are incorporated herein by reference.

In some embodiments, the filter media 32 can consist of the filter mediaor web alone or can include one or more additional components orstructures applied or assembled to the filter media 32 so long as theresultant filter media assembly 30 can at least be transitioned from therolled condition to the unrolled condition without significantlydamaging the structural integrity of the filter media assembly 30. Insome embodiments, the filter media can be repeatedly transitionedbetween the rolled and unrolled conditions without significantlydamaging the structural integrity of the filter media assembly 30. Thefilter media 32 of the assembly 30 can be self-supporting ornon-self-supporting. For example, where the filter media assembly 30consists of the filter media 32 alone, the filter media or web can beself-supporting or non-self-supporting. In some embodiments, where thefilter media assembly 30 consists of the filter media or web 32 and asupport structure, the filter media 32 can be non-self-supporting withan additional supporting structure rendering the filter media assembly30, as a whole, to be self-supporting. For example, the filter media 32can be wire-backed. As used herein, the term “self-supporting filtermedia or web” can describe at least one of the following conditions: (1)a filter media or web that is deformation resistant without requiringstiffening layers, adhesive or other reinforcement in the filter mediaweb; or (2) the filter media generally maintains its shape whensubjected to an airstream as described, for example, in U.S. Pat. No.7,169,202 to Kubokawa, the entire teachings of which are incorporatedherein by reference; or (3) a web or media having sufficient coherencyand strength so as to be drapable and handleable without substantialtearing or rupture. As used herein, the term “non-self-supporting” candenote an air filter media that is not capable, in the absence of asupport frame and/or a support grill, of withstanding the forcesencountered due to typical air flow.

In some embodiments, the retractable air filters 20 are useful inprotecting users from outside air quality contaminants As discussedabove, an electrostatically charged media 32 may be used. Additionalmulti-functional media grades, which incorporate activated carbon orother materials for purifying gas-phase pollutants, may also beincorporated into the filter media assembly 30. By incorporating anextended surface area and by covering moderate portion of the window, incombination with using a low pressure drop web enabled by theelectrostatic charging, a reasonably low pressure drop can be achievedfor the filter, which may help provide moderate airflow through thefilter.

FIGS. 4A-4C illustrate aspects of the materials and construction of anexemplary retractable filter 120, similar to retractable filter 20,installed in a sliding-type window 180, which can be either single ordouble hung. Sliding windows are predominant in North America and China.Attachment of the retractable filter 120 to a window 180, with orwithout housing 150, may be either permanent or semi-permanent. In someembodiments, attachment mechanisms 190, 192 provide secure holding ofthe retractable filter 120 to the window 180 because the attachmentpoint may undergo moderate stress from the inner spring forces as thefilter media assembly 130 is extended and retracted. Some exemplarypermanent fixation options include nails, screws, and certain types ofadhesives. In some embodiments, the attachment is semi-permanent, suchas using Command™ strips, adhesively backed interlocking hooks, rareearth magnets, etc. The housing 150 may be attached to the window frame182 (or surrounding structures) in the major plane of the window, or itmay be attached to the window frame 182 (or surrounding structures)perpendicular to the major plane of the window 180. In anotherembodiment, the housing 150 may not be mounted to the window frame 182at all, and may rather be pinched between the window sash 184 and thewindow frame 182. When expanded, the side edges 138, 140 of the filtermedia assembly 130 can be attached to the window frame/sill members withmechanical or adhesive components.

Finally, similar to the vertical sliding window 180 of FIGS. 4A-4Cdiscussed above, FIG. 5 illustrates an exemplary retractable filter 220installed in a horizontal sliding window 280. In some embodiments, thehousing 250 of the retractable filter 220 is attached at one end of thewindow 280, the window 280 is partially opened, and the filter mediaassembly 230 is expanded to cover the window gap. It is noted that asmall gap may be created between the two window segments, allowing airto flow from the outside between the two window segments and bypassingthe filter media assembly 230 to gain entry to the indoors. In someembodiments, this bypass may be avoided by the use of a piece of foam,weather-stripping, etc. (not shown).

The air filters of the present disclosure can be placed in any desiredframe or housing. Some exemplary frames are described in, for example,U.S. Patent Application No. 62/041,496 and 62/041,499, both of which areincorporated in their entirety herein. The air filter assembly of thepresent disclosure can be used in a powered air filtration system suchas, for example, that described in U.S. Patent Application No.62/041,501, incorporated herein in its entirety. The air filter assemblyor media of U.S. Pat. No. 62/206,928 can be used in the air filters ofthe present disclosure.

The terms first, second, third and the like in the description and inthe claims, are used for distinguishing between similar elements and notnecessarily for describing a sequential or chronological order. It is tobe understood that the terms so used are interchangeable underappropriate circumstances and that the embodiments of the inventiondescribed herein are capable of operation in other sequences thandescribed or illustrated herein.

All references mentioned herein are incorporated by reference in theirentirety.

Moreover, the terms top, bottom, over, under and the like in thedescription and the claims are used for descriptive purposes and notnecessarily for describing relative positions. It is to be understoodthat the terms so used are interchangeable under appropriatecircumstances and that the embodiments of the invention described hereinare capable of operation in other orientations than described orillustrated herein.

The recitation of all numerical ranges by endpoint is meant to includeall numbers subsumed within the range (i.e., the range 1 to 10 includes,for example, 1, 1.5, 3.33, and 10).

Those having skill in the art will appreciate that many changes may bemade to the details of the above-described embodiments andimplementations without departing from the underlying principlesthereof. Further, various modifications and alterations of the presentinvention will become apparent to those skilled in the art withoutdeparting from the spirit and scope of the invention. The scope of thepresent application should, therefore, be determined only by thefollowing claims and equivalents thereof.

1. An air filter comprising: filter media assembly configured in a roll, the filter media assembly including filter media having a leading end opposite a trailing end and first and second opposed side edges extending between the leading end and the trailing end.
 2. The air filter of claim 1, further comprising: a housing for containing the filter media assembly.
 3. The air filter of claim 2, wherein the leading edge can be releasably retained on at least one of the exterior or interior of the housing.
 4. The air filter of claim 2, wherein the filter media assembly is replaceable within the housing.
 5. The air filter of claim 1, wherein at least one of the leading edge and the trailing edge includes a looped structure, a hooked structure, and/or a fastening device.
 6. The air filter of claim 1, wherein the first end includes a handle.
 7. The air filter of claim 1, wherein the filter media assembly is retractable on the roll.
 8. The air filter of claim 1, wherein the roll includes a central member that is under spring tension.
 9. The air filter of claim 8, wherein the central member provides stopping points.
 10. The air filter of claim 1, wherein the filter media assembly includes sufficient filter media for multiple uses.
 11. The air filter of claim 1, wherein the filter media assembly includes separation and/or perforation lines or points.
 12. The air filter of claim 1, further including a hinged attachment mechanism.
 13. The air filter of claim 12, wherein the hinged attachment mechanism is combined with the housing or attached to the central member.
 14. The air filter of claim 13, wherein the hinged attachment mechanism is rotatable.
 15. The air filter of claim 1, wherein the filter media is at least one of moisture-resistant, moisture-repellant, electrostatically charged, an electret nonwoven web, and/or not electrostatically charged.
 16. The air filter of claim 1, wherein the filter media includes at least one of carbon, activated carbon, a nonwoven, a thermoplastic, a thermosetting material, a porous foam, fiberglass, paper, a high loft spunbound web, a low loft spunbound web, a meltblown web, and/or bi-modal fiber diameter meltblown media.
 17. The air filter of claim 1, wherein the filter media is pleated.
 18. The air filter of claim 1, wherein the filter media is at least one of self-supporting and non-self-supporting.
 19. The air filter of claim 1, further including a cutting device capable of cutting the filter media to a desired size.
 20. The air filter of claim 19, wherein the cutting device is integrated into the housing.
 21. The air filter of claim 1, wherein the air filter is a window air filter.
 22. A kit, comprising: an air filter of claim 1; and a cutting device capable of cutting the filter media to a desired size.
 23. The kit of claim 22, wherein the cutting device is integrated into the housing.
 24. A kit, comprising: an air filter of claim 1; and an attachment device capable of permanently or semi-permanently attaching the air filter to a window.
 25. The kit of claim 24, wherein the attachment device is at least one of a nail, a screw, a hook, an adhesive, and/or an adhesive backed interlocking strip. 